1. Field of the Invention
This invention relates to a new and improved bottle cap having a smooth wall plug for use in water dispensers. More particularly the invention relates to a cap of the "non-spill" type used with a water dispenser which displaces a plug from a well in the cap to permit water to be dispensed and then, when the bottle is removed from the dispenser, causes the plug to be replaced in the well. Further, the invention relates to structure of the main cap which fits on the bottle.
2. Related Art
Prior patents of the general type of the present application include U.S. Pat. Nos. 5,370,270 and 5,232,125 which disclose a plug closing off a central sleeve in a cap fitting on the neck of a water container. The plug is formed with a plug sleeve fitting into the cap sleeve and an end closing off the plug sleeve. Such a cap is intended to be used on a container which is inverted and lowered into a dispenser to prevent spillage during inversion. However, such a plug has been retained in the cap sleeve by a snap-in fit, wherein an internal bead in the sleeve snaps into a groove in plug skirt. The present invention differs from such structures in that the plug is retained in place in the cap sleeve by friction, rather than a snap fit, until such time as a probe on the dispenser has locked onto the plug.
Prior cap structures shown in U.S. Pat. Nos. 5,513,763 and copending application Ser. No. 08/436,936 are used with screw threaded container necks and are formed with threads which are shaped so that the cap cannot be unscrewed so long as the cap is intact. The present application includes such a feature but the thread structure is considerably simplified.
U.S. Pat. No. 5,121,846 discloses a cap which seals onto the neck of a large container. The present invention in one of its embodiments employs such a cap but incorporates therein a central sleeve closed by a plug held therein by friction.